Apparatus for recovering sulphur



Jal 6, 1942- J. P. WHITE APPARATUS FOR RECOVERING SULPHUR 2 Sheets-Sheetl Filed Feb. e, 1941 I rentar Jan. 6, 1942. J. P. WHITE l APPARATUS FORRECOVERING SULPHUR Filed Feb. 6, 1941 2 Shee'cs--Sheell 2 Im'entorPatented Jan. 6, 1942 UNITI-:Dv STATES PATENT OFFICE mf.f.lf l

Application February 6,1941, Serial No. 377,734

v(ci. 26a- 3) 2 Claims.

My invention relates to improvements in apparatus for the recovery ofsulphur from wells by combined application of electrically generatedheat and fluid pressure to the contents of the well, whereby the sulphurbearing matter is rendered into fluid form and hydraulically lifted tothe surface of the earth, and the primary object of my invention is toprovide simple and eiiicient arrangements of this character.

Other important objects and advantages of my invention will be apparentfrom a reading of the following description taken in connection with theappended drawings, wherein preferred embodiment of the apparatus of theinvention is shown.

In the drawings:

Figure 1 is a general fragmentary and vertically contracted sectionalelevational view taken through a well and a portion of the casing.

Figure 2 is an enlarged fragmentary longitudinal transverse sectionalview taken through the heating means.

Figure 3 is an enlarged horizontal sectional view taken through Figure 2along the line 3 3.

Figure 4 is an enlarged horizontal sectional view taken through Figure 1along the line 1 4.

Figure 5 is an enlarged horizontal sectional view taken through Figure 2along the line 5 5.

Referring in detail to the drawings, and particularly to Figure 1thereof, the method of the present invention is carried out by drillinga well hole 5 to the top 6 of the sulphur bearing formation 1, the hole5 being of sufficient diameter to accommodate permanent setting of thesteel casing 8 which is preferably 12 inches in diameter. Below andpermanently sealed to the lower end of the casing 5 by means of a leadseal 9 is a perforated steel pipe I0, commonly referred to as a liner,which extends into the sulphur bearing formation 1. Within the liner I0and casing 8 is suspended a pipe II, preferably about 3 inches indiameter, commonly referred to as tubing,to the lower end of which isattached the heating unit which is generally designated I2. The tubingII and the heating unit I2 are arranged to be raised or lowered insidethe well casing and liner and suspended at any desired level. Methods incommon use for raising and lowering the same, such as used in oil orsulphur well drilling and operating, are satisfactory for the purpose.

Strapped or otherwise attached as indicated by the numeral I3 to theoutside of the tubing II is a conduit I4 containing two electricalconducheating unit I2. The conduit protects these cables against foulingor jamming against the sides of the casing or liner, the elements I3acting as guards and being conveniently spaced along the outside of thetubing.

The heating unit I2 is constructed of two concentrically spacedcylinders I5 and I6 which are hermetically sealed, providing an annularspace in which the longitudinally arranged electrical heating coils I'Iare supported for generating the heat necessary for the liquefaction ofthe sulphur in the formation 'I. The inner cylinder I6 is similar inform to the tubing II and a sleeve I8 threadably connects the upper endof the inner cylinder I8 and the lower end of the tube II as shown inFigure 2. The outer cylinder I5 is considerably larger than the innercylinder, being preferably about 8% inches inside diameter, beingswedged at its top and bottom to the inner cylinder I6, or equivalentlyis threadably connected by tapering elements I9 and 20, respectively. Asindicated in Figure 3 of the drawings the various heating coils I1 aresupportably located in flutes or grooves 2| in a suitable cylindricalinsulator 22 surrounding the inner cylinder I6, the heating coils beingconnected in series to upper and lower conductor rings 23 and 24,respectively, to which the conductors 25 and 26 in the cable conduit' I4are respectively connected. The cable I4 passes through a grommet 21 inthe upper tapered element I9 shown in Figure 2.

Secured to the lower end of the inne'fcylinder I6 below the taper 20 isa perforated bull plug 30 to act as a strainer to exclude solids andforeign bodies which might otherwise jam the tubing Il or the jet line3| which extends down through the tubing II and the inner cylinder I6 toa position within the bull plug shown in Figure 2.

The heating unit attached to the tubing II is suspended inside theperforated liner I0 as described above, the perforations in the linerpermitting the water in the formation 1 to enter the liner. Thissub-surface water being under considerable pressure may consequently beraised to a very much higher temperature than its boiling point atatmospheric pressure, without vaporzing. By contact with the heatingunit I2 this sub-surface water is raised to a temperature above themelting point of the sulphur. Therefore, cold water from without willtend to displace the heated water inside the liner, and the circulationthus established will bring the hot tor cables for supplying electriccurrent to the water into contact with,4and thereby liquefy the sulphurin place in the sulphur-bearing formation. The molten sulphur, beingheavier than the water, will sink to the bottom of the formation, fromwhich point it is raised to the surface of the earth in a manner t'o bedescribed below.

The jet line 3i extends from the bull plug 30, through the tubing il tothe top of the well where it traverses the cap 32 closing the upper endof the tubing il and is connected to an air compressor 33 supported onthe surface 34 of the earth. The .compressor 33 is arranged to force hotcompressed air, at a temperature above the melting point of the sulphur,down the jet line 3l at a pressure suiilcient to raise the moltensulphur in liquid form to the surface of the earth. This molten sulphuris raised through the tubing il outside of the jet line. A convenientmethod of obtaining compressed air at the desired temperature is heatingof the air by the same Diesel power unit used for generating electricpower for the heating unit. The hot compressed air forced down throughthe jet line forces the molten sulphur from the bottom of the wellupwardly on the same principle that oil or water wells are jetted. Asthe molten sulphur moves upwardly, a suction is set up which draws moreofthe molten substance, liqueed by the hot water circulation, to thejet, at the bottom of the heating unit. The numeral 35 generallydesignates diagrammatically suitable rigging for operating the devicedescribed. In addition there is shown a flexible tube 36 connected by agooseneck 31 to the cap 32 of the tubing whereby the molten sulphur isled off to the flow line, from whichthe molten sulphur is dischargedinto pits. The generator of the electric power supply unit is generallydesignated by the numeral 38, the conduit I4 being shown run overpulleys 39 and 4l) on the rig 35.

An upper packer 4I of conventional arrangement is placed around theportion of the inner cylinder of the heating unit extending above theupper taper I9 to seal the unit in the liner I0 and the lower packer orback pressure valve 42 seals the outer cylinder of the heating unit inthe perforated liner I0. Vertically spaced spacers 43 and 44 are mountedon the tubing Il to concentrically space the tubing Il from the sides ofthe casing 8 when raising and lowering the heating unit.

Although I have shown and described herein a preferred embodiment of theapparatus and of the method of the present invention, it is to beunderstood that I do not wish to limit the application o1 the inventionthereto, beyond the scope of the subjoined claims.

Having described the invention, claimed as new is:

1. In combination, a drill hole extending to the top of a sub-surfacesulphur bearing formation containing water, a casing lining said hole, aperforated liner sunk in said formation and sealed to the lower end ofsaid casing, a heating unit situated within said perforated liner insaid formation, said heating unit containing heat generating means forcontact heating of the Water from said formation entering saidperforated liner to a temperature above the melting point of thesulphur, said heating unit comprising an inner cylinder surrounded bysaid heat generating means and open at its lower end, tubing connectedto the upper end of said inner cylinder and extending upwardly in spacedrelation to said casing to the surface of the earth, means sealing saidunit in said perforated liner, a jetting pipe depending within saidtubing and through said inner cylindenand a source of hot air connectedto the upper end of said jetting pipe for applying air to the moltensulphur below said heating unit at a temperature higher than the meltingpoint of the sulphur and at sufficient pressure to force the moltensulphur through said inner cylinder and tubing to the surface of theearth.

2. The combination recited by claim 1 wherein said heat generating meanscomprises electriwhat is cal heating coils, a. jacket enclosing saidheating coils, a protected conduit containing conductors to the coils,said conduit being connected to the outer side of said tubing. andextending to the surface of the earth, and current supplying meansconnected to said conductors.

JOHN PATRICK WHITE.

